Linda R. Tripp, whose secret tape recordings launched the perjury and obstruction-of-justice probe of President Clinton, has provided grand jury testimony about at least two other matters under investigation by independent counsel Kenneth W. Starr, according to court papers filed by Starr's office.

Tripp is aiding prosecutors looking into possible criminal activities during the 1993 firing of seven career employees in the White House travel office, as well as allegations that the Clinton White House improperly obtained confidential FBI files on hundreds of former Reagan and Bush administration employees, court papers said.

Prosecutors publicly revealed details about the scope of Tripp's assistance in a move to delay her testimony in a civil suit stemming from "Filegate," the controversy surrounding the FBI files. Judicial Watch, a conservative watchdog group, wanted to take Tripp's deposition yesterday and intended to question her for six hours. However, at the request of Starr and Tripp, U.S. District Judge Royce C. Lamberth postponed questioning indefinitely.

Deputy independent counsel Robert J. Bittman contended in court papers that Tripp should not be forced to testify in a civil case when the various criminal investigations are in "extremely sensitive stages." He noted that Judicial Watch's founder, Larry Klayman, planned to videotape Tripp's deposition and make it public. Doing so could aid grand jury targets, Bittman wrote. The court papers, filed under seal, were made public by Lamberth yesterday.

"The United States and the grand jury are deeply involved in several broad criminal investigations which reach to the highest levels of the federal government," Bittman wrote. He called Tripp, who spent eight days testifying before a grand jury at the federal courthouse this summer, "an important witness" and said, "Any premature disclosure of her knowledge or materials could seriously undermine the United States and the grand jury's efforts."

Tripp worked at the White House in both the Bush and Clinton administrations. Although her FBI file was among the hundreds that were obtained by Clinton administration officials, she is not part of Klayman's lawsuit. She was transferred to the Pentagon in 1994. It was there that she befriended Monica S. Lewinsky, whom she later secretly taped talking about an affair with Clinton.

Klayman argued in his court papers that Tripp was "uniquely positioned to witness the illegalities of Filegate." He urged Lamberth to permit the testimony to go forward so that her account can quickly become public.

But Bittman said that delaying Tripp's appearance until the grand jury work is over could ultimately help Klayman's case. "If the grand jury proceedings result in prosecutions or public report, [Klayman] may have access to much if not all of the evidence adduced in the criminal investigation," Bittman wrote. "Further congressional hearings may reveal even more information."